Answer:
A. singular subject and a singular verb
Step-by-step explanation:
Everyone has the right to choose what to eat for lunch.
In the given sentence, the subject "everyone" is an indefinite pronoun, singular in number. Even though it sounds like it refers to a lot of people or more than one person, it is a singular noun.
And the word "has" is the verb in the given sentence, which is singular in number. “Has” is used for a singular third person.
So, considering the given sentence, it has a singular subject and a singular verb.
Thus, the correct answer is option A.